Method of purifying cracked petroleum vapors



.2.1M Clay Teeder Feb. 24, 1931. c. B. WATSON ET AL. 1,793,885

METHOD OF PURFYING CRACKED PETROLEUM VAPORS Filed Aug. 2l, 1928 3rd Clay Teder Vaporz er Y Patented Feb. 24, 1931l ,PATamy OFFICE communs B. wA'rsoN Nn RUDOLPH c.

OSTEBSTROM, OF CHICAGO, ILLINOIS, AS-

SIGNOBS T THE PURE OIL COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F OHIO Y METHOD 0F IPUBIFYING CRACKED PETROLEUH VAIPOBS application med .august 21, 192s. semi no. $00,996.

such methods considerable difliculty has been.

encountered in stabilizing the color of the '15 completed motor fuel product, and particularly ineffecting the complete and permanent removal of the gum content thereof. A com mon method employed by oil refiners in efforts to control these conditions consists in passing oil vapor, following conversion, through a removed from the system so' that the oil.

' vapor is constantly maintained in contact with fresh treating material in order that the system may operate at a uniform degree of efficiency at all times.

A further object ofthe invention is to' provide for a substantially complete removal of l the undesirable gum and color producing compounds from the oil vapors and at the same time to use but a minimum quantity of the treating f material, in order that the sys- 5 ing,A wherein:

tem may be operated economically as well Figure 1 represents a diagrammatic view of apparatus which may be employed in connection with the invention and Figure 2 is an enlarged detail view.

Referring more particularly to the drawings, the numeral 1 designates 'an oil converter o'r heater. 'This converter or heater may be of any desired form and construction wherein theoil, passing through the same, s heated to a` converting temperature of for example 10000 F. so as to vaporize the oil and effect its molecular decomposition.` The converted oil in vapor form passes from the converter by way of a pipe line 2 and into a coolerI from which it is led by a line 8a, to a fractionating tower 3b. @This tower is provided with a plurality of angularly disposed st'ationary baffle walls 4, which are situated in the upstandingcolumnfportion 5 m :of the tower..

Entering the line 3a is a clay feeding duct 6 which, in this instance, is 'provided with a worm or conveyor 7, driven, for example, by a .variable speed motor 8. The inlet end of the duct 6 is connected with a clay con- 75 taining hopper 9 and it will be seen that by operating the motor 8 the clay, at a controlled rate of flow, may be introduced intoV the pipe 3a where it is brought into intimate Contact with the oil vapors passing from the converter 1 to the fractionating column 3b. The heavier fractions, or what may be termed the undesirable fractions of the oil vapor, are absorbed by the clay and drop into the enlarged bottom 10 of the fractionating column 3.

The lighter oil lfractions -or yapors arise in the fractionating tower and follow the customary tortuous 'path while passing upwardly through the tower by reason of their Contact with the baille walls 4:. This'results, as usual, in the separation of the high boiling point fractions lof the oil from those of lower boiling point, the latter passing outwardly from the tower by way of the overhead line 11, while the liquefied or condensed fractions move downwardly, contacting with the ascending va' ors, so as to scrub lthe latter, and' to collect'm the bottom por- 100 tion of the tower the heavier or liquefied portions.

It is also preferable in some instances to provide a second clay introducing unit in connection with the tower as indicated at 12 in the drawings. This unit corresponds substantially with the previously describedunit vlitt and may consist of the hopper 13, the feedingr duct 14, and the motor driven worm 15. When-the second unit is in operationr the clay ejected therefrom contacts with a subst antially conical and stationaryy deflector 16 arranged in or near the to of the tower 3. This enables the clay by falling through the column 5, to contact uniformly with the ascending oil vapors, thereby permitting the clay to remove from such vapors the undesirable cmpoundsabove mentioned and to permit such compounds and the clay to fall into the bottom of the tower. The bottom of the tower is provided with an outlet line 17 which leads to re-,run apparatus (not shown) for the purpose of further heat treating thel clay and heavy polymerized oil compounds to recover the lighter fractions of the oil which may be therein contained.

The overhead line 11 extends to an inclosed vessel 18 and if. desired, there may be situated in the line 11 a third clay introducing unit 19. This unit'inay also correspond with the previously described units and in this instance has been shown as consisting of a hopper 20a feeding duct 21, a worm 22, and a driving motor 23. Thus the vapors passing through the line 11 may be again intermingled with suitable quantities of finely divided clay, such as\fullers earth, for the purposev of procuring a further purification v. of the oil vapors. The entrained clay introduced into the line 11 is carried by the oil vaporvinto theves'sel 18, in which there ,v takes place a separation of the vapors or yso lighter fractionsl of the oil from the heavier liquid fractions. The latter, together with the clay, pass-oil"I by way of a line 24, leading from the bottom of the vessel 18, into a separator 25, in which the oil fractions are removed from the clay'or other treating material. The lighter fractions which enter the vessel18 pass overhead by way of a line 26 to a condenser 27, and the finally purihed products are then transferred to a storage tank28 as finished motor fuel. A gas separator may be employed in connection with the condenser 27 to effect the removal of the non-condensibles from the system. s

In view of the foregoing it will be seen that the present invention provides 4for the bringing of the treating materialinto very intimate contact with the oil vapors, and due to the intimacy of this contact there is effected first, ,an ellicient removal of the undesirable compounds from the oil and, secondA an economy in operation due to the relatively small quantity of treating material renveaees rand whilethe vapors are at high temperature, it having been found that the higher the temperature of the oil vaporthe more effective the treating material is in carr ing out its required functions. The clay w ich accumulates in the vessel 18 may be rejuvenated by cutting ed the oil How through a portion at leastof the line 11, and then introducing superheated steam into said line so that said steam will be brought into contact with the clay treating material which accumulates withln the vessel 18. Theintroduction of the steam or other inert gas liquefies the polymers or other heavy oil compounds contained in the clay so that said compounds may be removed from the clay and the latter again rendered suitable for effective operation.

It will be appreciated that the clay may be introduced into the system not only in the form of a inel divided dry material, but may be in the orm of al paste, semi-liquid, or liquid state, such as in solution. Again, the various clay introducing units ma operate simultaneously or may operate se ectively, depending u on operating conditions and the character o the oil being treated.

The chargin stock used by the system is contained in t e tank 29 and is forced by means of a pump 30 through a pi e line 31 into the cooler 3. This fresh col stock oil in the cooler 3 is intimately intermingled charged at high temperatures, preferably above 1000 F., from the converter so that through the resultant heat interchange the cracked vapors are cooled below decomposition temperatures. The vapors from the cooler 3 pass through the line 3a into the purifying and fractionatin apparatus described, whereas the liquefiedl portions of the stock in the bottom of the cooler is removed to a hot oil tank 32 and is then pumped by way of a pipe line 33 into a vaporizing unit 34. In this unit the temperature of the oil is raised to a proximately 650 F., and the vapors are ischarged by way of the line 35 into an eva orator 36. In this evaporator the unvaporlzed portions of the oil are permanently removed from the system by means of the outlet 36 usually as fuel oil, whereas the lighter vaporized portions pass overhead through the pipe line 37 and into the cn' within the setting o f'the converter is such as to effect the heating of the oil to a cracking temperature in excess of 1000 F. Following such heating the vapors 'are introduced into the cooler 3 where their't'emperature is immediately lowered to below'600 F. by being intermingled withd the fresh charging stockintroduced into the cooler by way of the line 31.

What is claimed is:

1. In a method of converting purifying and decolorizing petroleum oils, the step of passing petroleum oils through a heating zone and in there subjecting the oils to heat sufficientto vaporize the oils and raise the temperature thereof to above 10000 F., cooling theV oils immediately upon their release from the heatding zone to a temperature not in excess of 600 F., passing the vapors remaining following the cooling operation into a fractionating zone, and introducin into said vapors between the cooler and t e fractionating zone a quantity of a refining agent having substantially the properties of fullers earth.

2. In a method of treating petroleum oils, the steps of subjecting petroleum oil to temperatures sufficiently high to vaporize and effect molecular decomposition thereof, then cooling the oils to a temperature sufficient to arrest conversion reactions therein, passing the remaining vapors from the cooling to a fractionating zone and introducing into such vapors during their passage between the cooling and fractionating zones a body of purifying material having substantially the properties of fullers earth. y

3. In a method of treating petroleum oils,

l the steps of heating petroleum oil under such conditions as to vaporize and effect molecular decomposition thereof, introducing the oils a following such heat treatment into a cooling zone to lower the temperatures of the vapors sufficiently toarrest conversion reactions, then passing the remaining vapors at a temperature excess of 450 F. from the cooling to a fractionating zone, and introducing into such vapors while the latter are in transit between said zones predetermined quantities of fullers earth.

4. In a continuous method of converting and purifying petroleum oils, the steps of heat treating petroleum oilsto vaporize the same and to break down the higher boiling point compounds thereof into compounds of relatively lower boiling points, passing said vapors from said heating zone in a confined continuously flowing stream to a fractionating zone, and introducing into said vapors flowing between said zones regulatable quantities of purifying material of the fullers earth. y,

5. In a continuous method of converting and purifying petroleum oils, the steps of,

heat treatingpetroleum oils to vaporize the same and to break down the higher boiling point com ounds thereof into compounds of relatively ower boiling points, passing said vapors from said heating zone in a confined continuously owing stream to a fractionating zone, and introducing into said vapors flowing between said zones regulatable quantities of adsorptivepurifying material of the nature of fullers earth, subjecting said vapors to fractionation and separately removing the lighter and vaporous fractions from a liquefied clay-polymer fraction formed in said fractionating zone.

6. A method of treating petroleum oil l which consists in subjecting petroleum oil to a temperature suiiiciently high to vaporize and effect molecular decomposition thereof, cooling said vapors to a temperature sufficient to arrest conversion reactions therein, removing oil liquefied by said coolin passing the remaining vapors from the coo ing to a fractionating zone, introducing into said vapors between said Zones predetermined quantities of an adsorptive purifying material of the nature of fullers earth, removing purified vapors from said fractionating zone and condensing said vapors.

7. A methodV of treating petroleum oils comprising, subjecting etroleum oil to-a temperature suiiiciently high to vaporize and effect molecular decomposition thereof, cooling said vapors to a temperature suicient to arrest conversion reactions therein, removing oil liquefied by said cooling from said vapors, passing-the remaining vapors from the cooling te a fractionating zone, introducing predetermined quantities of a purifying material of the nature of fullers earth into said vapors between said zones, sub'ecting said vapors to fractionization in sai fractionating zone, separately removing a liquefied clay-polymer fraction formed in said fractionating zone,

separately removing the li hter vaporous fractions from the fractionatin zone, introducing a purifying material having the properties of fullers earth into said purified vapors from said fractionating zone, and then separating said vapors from said purifying material.

8. In a method of treating cracked petroleum vapors, the steps of continuously passing 4 messes '9. A continuous method of converting and purifying petroleum oils which consists in subjecting petroleum oil to a temperature sufficiently high to-vaporize and eHectA molecular B decomposition thereof, cooling said vapors to a temperature suicient to arrest conversion reactions therein, removing` oil liquefied by said cooling'from said vapors, passlng the remaining vapors from the cooling to a frac-k m tionating zone, introducing inely divided purifying agent of the nature of fullers earth. into the upper portion of-said fractionating zone, permittin said inely dividedpurifying agent to 'fal in substantially dry state 15 through such vapors in counter-current relation thereto, s e arately removing partially purified vapors rom the top of said zone and purifyin agent and heavier liquefied fractions of 011 from the bottom of said zone, pass= 2b ing the partially purified vapors from the top of said fractionating zone to a separating zone, introducing nely divided purifyin agent of the nature of ullers earth into sai partially purified vapors between said frac- 25 tionating and separating zones, separating purified vapors from the purifying agent in Said separating zone,` and separatel condensing the purified vapors from sai separating zone. -39 In testimony whereof we alix our signatures.

' CORNELIUS B. WATSON.

RUDOLPH C. OSTERSTROM. 

